他只看重外表的选择暴露了他的肤浅。

His choice, based solely on looks, exposed his superficiality.

superficiality 是由形容词 superficial（肤浅的）加上名词后缀 -ity 构成的名词，表示"肤浅、浅薄"的性质或状态。superficial 本身由前缀 super-（在...之上）和词根 face（表面）组成，字面意思是"停留在表面的"。